Objective To evaluate the value of Materialise's interactive medical image control system (MIMICS) in the computer aided surgery, and to offer a reliable system for precise surgical planning and good effect of orthognathic surgery. Methods Based on CT images, geometric characteristics of 2 patients' head were collected for a 3D reconstruction of the human head. Skull, skin, and submucous tissue were reconstructed and optimized separately by MIMICS 10.01. Surgeries were simulated and the soft tissue deformation was predicted according to the surgical planning of experienced surgeons. Results Mesh of skull, skin and submucous tissue were constructed manually for 2 patients. Surgical procedures were simulated and the prediction of soft tissue deformation was realized by MIMICS, which could be visualized in any angle. Conclusion MIMICS is a helpful digital tool for computer aided surgery and the prediction of soft tissue deformation. MIMICS is also a 3D visualization system for orthognathic surgeries, by which surgeons could realize the surgical planning, revising,and the patient-doctor communication on the computer screen.